In many screens, in particular those with liquid crystal displays, optical polarizers are used. However, as well as acting as spectral filters in connection with liquid crystal displays, polarizers are also used to prevent light from the area surrounding the screen from entering the screen structure and leaving it again after being reflected in the interior of the screen. If ambient light were able to enter the screen unhindered and be reflected back out again, this would not only reduce the visibility of the screen display but also result in an undesirable appearance of the screen when it is switched off.
In the structure of a screen, polarizers are conventionally used in the form of layers within a more complex layer structure. In order to prevent ambient light from entering the layer structure as described above, it is advantageous if a polarization layer is arranged in an upper region of the layer structure, that is to say close to a screen surface. Thus, a polarization layer is often arranged immediately beneath a screen cover, conventionally a cover glass. Further components of the screen structure, such as, for example, in the case of a touch screen, a contact sensor layer or elements of a display assembly group, can then be arranged beneath the polarization layer.
In currently common methods for producing a screen of the described type, a polarization layer is laminated to the rear side of the cover glass by means of optically clear adhesive. In addition, a layer of optically clear adhesive is laminated to a substrate in the screen structure, for example a touch sensor layer provided beneath the polarization layer, or, when liquid adhesives are used, a liquid adhesive layer is applied. The cover glass including the polarization layer and the substrate provided with adhesive can then be laminated to one another in a further method step.
The described methods for producing screens having polarization layers have been found to be comparatively complex in practice. The same is true for the use of polarizers in other fields, such as, for example, in the case of light-emitting decorative elements.